The genus Anthracothecium is re-reported for the territory of Russia. The article discusses that A. speciosum f. speciosum was mistakenly included in the lists of lichens of Russia, of the south of the Far East and of Shikotan Isl., and also that A. speciosum f. iturupiense morphologically and anatomically corresponds more closely to the genus Pyrenula. Thus, the tropical genus Anthracothecium is represented in Russia by one species, Anthracothecium australiense reported here to the Kunashir Island. This is a first record of the species in Russia which has previously been known to Australia, Oceania (New Guinea), Asia (Japan and China), North and South America (Brazil, Argentina). The species is characterized by large, brown muriform ascospores with thin walls, as well as immersed, erumpent, and semi-immersed, black, globose perithecioid ascomata (0.5–)0.7–1.0 mm wide with a short neck and lateral ostiole. The data on distribution, ecology, and distinctive features of the species as well as photos are provided.
Каганов et al. (2026) studied this question.